Ruminant Urolithiasis: II. Histochemical Studies in Experimental Ovine Calculosis

Abstract
Histochemical studies on the urinary system on normal castrated male sheep and on animals on an experimental diet with complete or partial urethral occlusion from impacted calculi revealed the following. In the latter animals, an increase in periodic acid-Schiff (PAS) positive accumulations was noted within the cells of the proximal and distal convoluted tubules, on the brush borders of the proximal convoluted tubules, and within the cells of the collecting tubules. Increased PAS-positive material was also observed in casts within and upon the surfaces of the transitional epithelial cells of the renal pelvis and urinary bladder. The matrices of calculous material isolated simultaneously from the urinary bladders of these sheep exhibited similar staining characteristics. It is concluded that carbohydrate-protein complexes, important in matrix formation, may originate from sources other than the transitional epithelium.